1. Field of the Invention
This invention relates generally to the thermal interface between a semiconductor device and a thermal plate, and more particularly, to an apparatus and method for controlling the thickness of the thermal interface layer between a processor die and the thermal plate in a microprocessor device.
2. Description of the Related Art
In microprocessor devices, especially of the control collapse chip connection (C4) type, it is desirable to control the thickness of the thermal interface between the processor die and thermal plate. A continous and consistent thermal path will not be formed between the processor die and thermal plate if a controlled interface thickness is not maintained. This will impede the cooling of the processor die and other components of the microprocessor. It is therefore desirable that the thickness and thickness tolerance of the thermal interface be tightly controlled.
In the semiconductor industry, it is common for original equipment manufacturers (OEMs) to purchase microprocessors that have not been fully packaged. Often, the OEMs complete the packaging steps during the final assembly steps of the end product. As a result, many OEMs are left with the task of applying the thermal interface layer between the processor die and thermal plate. For the tolerance of the thermal interface layer to be tightly controlled, this packaging step is complex and costly for the OEMs.
The present invention is directed at reducing the complexity and thus cost associated with precisely and reliably controlling the thickness of the thermal interface layer for the OEMs during final assembly of the end product.